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Diffstat (limited to 'src/jinja2/compiler.py')
| -rw-r--r-- | src/jinja2/compiler.py | 1754 |
1 files changed, 0 insertions, 1754 deletions
diff --git a/src/jinja2/compiler.py b/src/jinja2/compiler.py deleted file mode 100644 index abdbe6da..00000000 --- a/src/jinja2/compiler.py +++ /dev/null @@ -1,1754 +0,0 @@ -"""Compiles nodes from the parser into Python code.""" -from collections import namedtuple -from functools import update_wrapper -from io import StringIO -from itertools import chain -from keyword import iskeyword as is_python_keyword - -from markupsafe import escape -from markupsafe import Markup - -from . import nodes -from .exceptions import TemplateAssertionError -from .idtracking import Symbols -from .idtracking import VAR_LOAD_ALIAS -from .idtracking import VAR_LOAD_PARAMETER -from .idtracking import VAR_LOAD_RESOLVE -from .idtracking import VAR_LOAD_UNDEFINED -from .nodes import EvalContext -from .optimizer import Optimizer -from .utils import concat -from .visitor import NodeVisitor - -operators = { - "eq": "==", - "ne": "!=", - "gt": ">", - "gteq": ">=", - "lt": "<", - "lteq": "<=", - "in": "in", - "notin": "not in", -} - - -def optimizeconst(f): - def new_func(self, node, frame, **kwargs): - # Only optimize if the frame is not volatile - if self.optimized and not frame.eval_ctx.volatile: - new_node = self.optimizer.visit(node, frame.eval_ctx) - if new_node != node: - return self.visit(new_node, frame) - return f(self, node, frame, **kwargs) - - return update_wrapper(new_func, f) - - -def generate( - node, environment, name, filename, stream=None, defer_init=False, optimized=True -): - """Generate the python source for a node tree.""" - if not isinstance(node, nodes.Template): - raise TypeError("Can't compile non template nodes") - generator = environment.code_generator_class( - environment, name, filename, stream, defer_init, optimized - ) - generator.visit(node) - if stream is None: - return generator.stream.getvalue() - - -def has_safe_repr(value): - """Does the node have a safe representation?""" - if value is None or value is NotImplemented or value is Ellipsis: - return True - - if type(value) in {bool, int, float, complex, range, str, Markup}: - return True - - if type(value) in {tuple, list, set, frozenset}: - return all(has_safe_repr(v) for v in value) - - if type(value) is dict: - return all(has_safe_repr(k) and has_safe_repr(v) for k, v in value.items()) - - return False - - -def find_undeclared(nodes, names): - """Check if the names passed are accessed undeclared. The return value - is a set of all the undeclared names from the sequence of names found. - """ - visitor = UndeclaredNameVisitor(names) - try: - for node in nodes: - visitor.visit(node) - except VisitorExit: - pass - return visitor.undeclared - - -class MacroRef: - def __init__(self, node): - self.node = node - self.accesses_caller = False - self.accesses_kwargs = False - self.accesses_varargs = False - - -class Frame: - """Holds compile time information for us.""" - - def __init__(self, eval_ctx, parent=None, level=None): - self.eval_ctx = eval_ctx - self.symbols = Symbols(parent.symbols if parent else None, level=level) - - # a toplevel frame is the root + soft frames such as if conditions. - self.toplevel = False - - # the root frame is basically just the outermost frame, so no if - # conditions. This information is used to optimize inheritance - # situations. - self.rootlevel = False - - # in some dynamic inheritance situations the compiler needs to add - # write tests around output statements. - self.require_output_check = parent and parent.require_output_check - - # inside some tags we are using a buffer rather than yield statements. - # this for example affects {% filter %} or {% macro %}. If a frame - # is buffered this variable points to the name of the list used as - # buffer. - self.buffer = None - - # the name of the block we're in, otherwise None. - self.block = parent.block if parent else None - - # the parent of this frame - self.parent = parent - - if parent is not None: - self.buffer = parent.buffer - - def copy(self): - """Create a copy of the current one.""" - rv = object.__new__(self.__class__) - rv.__dict__.update(self.__dict__) - rv.symbols = self.symbols.copy() - return rv - - def inner(self, isolated=False): - """Return an inner frame.""" - if isolated: - return Frame(self.eval_ctx, level=self.symbols.level + 1) - return Frame(self.eval_ctx, self) - - def soft(self): - """Return a soft frame. A soft frame may not be modified as - standalone thing as it shares the resources with the frame it - was created of, but it's not a rootlevel frame any longer. - - This is only used to implement if-statements. - """ - rv = self.copy() - rv.rootlevel = False - return rv - - __copy__ = copy - - -class VisitorExit(RuntimeError): - """Exception used by the `UndeclaredNameVisitor` to signal a stop.""" - - -class DependencyFinderVisitor(NodeVisitor): - """A visitor that collects filter and test calls.""" - - def __init__(self): - self.filters = set() - self.tests = set() - - def visit_Filter(self, node): - self.generic_visit(node) - self.filters.add(node.name) - - def visit_Test(self, node): - self.generic_visit(node) - self.tests.add(node.name) - - def visit_Block(self, node): - """Stop visiting at blocks.""" - - -class UndeclaredNameVisitor(NodeVisitor): - """A visitor that checks if a name is accessed without being - declared. This is different from the frame visitor as it will - not stop at closure frames. - """ - - def __init__(self, names): - self.names = set(names) - self.undeclared = set() - - def visit_Name(self, node): - if node.ctx == "load" and node.name in self.names: - self.undeclared.add(node.name) - if self.undeclared == self.names: - raise VisitorExit() - else: - self.names.discard(node.name) - - def visit_Block(self, node): - """Stop visiting a blocks.""" - - -class CompilerExit(Exception): - """Raised if the compiler encountered a situation where it just - doesn't make sense to further process the code. Any block that - raises such an exception is not further processed. - """ - - -class CodeGenerator(NodeVisitor): - def __init__( - self, environment, name, filename, stream=None, defer_init=False, optimized=True - ): - if stream is None: - stream = StringIO() - self.environment = environment - self.name = name - self.filename = filename - self.stream = stream - self.created_block_context = False - self.defer_init = defer_init - self.optimized = optimized - if optimized: - self.optimizer = Optimizer(environment) - - # aliases for imports - self.import_aliases = {} - - # a registry for all blocks. Because blocks are moved out - # into the global python scope they are registered here - self.blocks = {} - - # the number of extends statements so far - self.extends_so_far = 0 - - # some templates have a rootlevel extends. In this case we - # can safely assume that we're a child template and do some - # more optimizations. - self.has_known_extends = False - - # the current line number - self.code_lineno = 1 - - # registry of all filters and tests (global, not block local) - self.tests = {} - self.filters = {} - - # the debug information - self.debug_info = [] - self._write_debug_info = None - - # the number of new lines before the next write() - self._new_lines = 0 - - # the line number of the last written statement - self._last_line = 0 - - # true if nothing was written so far. - self._first_write = True - - # used by the `temporary_identifier` method to get new - # unique, temporary identifier - self._last_identifier = 0 - - # the current indentation - self._indentation = 0 - - # Tracks toplevel assignments - self._assign_stack = [] - - # Tracks parameter definition blocks - self._param_def_block = [] - - # Tracks the current context. - self._context_reference_stack = ["context"] - - # -- Various compilation helpers - - def fail(self, msg, lineno): - """Fail with a :exc:`TemplateAssertionError`.""" - raise TemplateAssertionError(msg, lineno, self.name, self.filename) - - def temporary_identifier(self): - """Get a new unique identifier.""" - self._last_identifier += 1 - return f"t_{self._last_identifier}" - - def buffer(self, frame): - """Enable buffering for the frame from that point onwards.""" - frame.buffer = self.temporary_identifier() - self.writeline(f"{frame.buffer} = []") - - def return_buffer_contents(self, frame, force_unescaped=False): - """Return the buffer contents of the frame.""" - if not force_unescaped: - if frame.eval_ctx.volatile: - self.writeline("if context.eval_ctx.autoescape:") - self.indent() - self.writeline(f"return Markup(concat({frame.buffer}))") - self.outdent() - self.writeline("else:") - self.indent() - self.writeline(f"return concat({frame.buffer})") - self.outdent() - return - elif frame.eval_ctx.autoescape: - self.writeline(f"return Markup(concat({frame.buffer}))") - return - self.writeline(f"return concat({frame.buffer})") - - def indent(self): - """Indent by one.""" - self._indentation += 1 - - def outdent(self, step=1): - """Outdent by step.""" - self._indentation -= step - - def start_write(self, frame, node=None): - """Yield or write into the frame buffer.""" - if frame.buffer is None: - self.writeline("yield ", node) - else: - self.writeline(f"{frame.buffer}.append(", node) - - def end_write(self, frame): - """End the writing process started by `start_write`.""" - if frame.buffer is not None: - self.write(")") - - def simple_write(self, s, frame, node=None): - """Simple shortcut for start_write + write + end_write.""" - self.start_write(frame, node) - self.write(s) - self.end_write(frame) - - def blockvisit(self, nodes, frame): - """Visit a list of nodes as block in a frame. If the current frame - is no buffer a dummy ``if 0: yield None`` is written automatically. - """ - try: - self.writeline("pass") - for node in nodes: - self.visit(node, frame) - except CompilerExit: - pass - - def write(self, x): - """Write a string into the output stream.""" - if self._new_lines: - if not self._first_write: - self.stream.write("\n" * self._new_lines) - self.code_lineno += self._new_lines - if self._write_debug_info is not None: - self.debug_info.append((self._write_debug_info, self.code_lineno)) - self._write_debug_info = None - self._first_write = False - self.stream.write(" " * self._indentation) - self._new_lines = 0 - self.stream.write(x) - - def writeline(self, x, node=None, extra=0): - """Combination of newline and write.""" - self.newline(node, extra) - self.write(x) - - def newline(self, node=None, extra=0): - """Add one or more newlines before the next write.""" - self._new_lines = max(self._new_lines, 1 + extra) - if node is not None and node.lineno != self._last_line: - self._write_debug_info = node.lineno - self._last_line = node.lineno - - def signature(self, node, frame, extra_kwargs=None): - """Writes a function call to the stream for the current node. - A leading comma is added automatically. The extra keyword - arguments may not include python keywords otherwise a syntax - error could occur. The extra keyword arguments should be given - as python dict. - """ - # if any of the given keyword arguments is a python keyword - # we have to make sure that no invalid call is created. - kwarg_workaround = False - for kwarg in chain((x.key for x in node.kwargs), extra_kwargs or ()): - if is_python_keyword(kwarg): - kwarg_workaround = True - break - - for arg in node.args: - self.write(", ") - self.visit(arg, frame) - - if not kwarg_workaround: - for kwarg in node.kwargs: - self.write(", ") - self.visit(kwarg, frame) - if extra_kwargs is not None: - for key, value in extra_kwargs.items(): - self.write(f", {key}={value}") - if node.dyn_args: - self.write(", *") - self.visit(node.dyn_args, frame) - - if kwarg_workaround: - if node.dyn_kwargs is not None: - self.write(", **dict({") - else: - self.write(", **{") - for kwarg in node.kwargs: - self.write(f"{kwarg.key!r}: ") - self.visit(kwarg.value, frame) - self.write(", ") - if extra_kwargs is not None: - for key, value in extra_kwargs.items(): - self.write(f"{key!r}: {value}, ") - if node.dyn_kwargs is not None: - self.write("}, **") - self.visit(node.dyn_kwargs, frame) - self.write(")") - else: - self.write("}") - - elif node.dyn_kwargs is not None: - self.write(", **") - self.visit(node.dyn_kwargs, frame) - - def pull_dependencies(self, nodes): - """Pull all the dependencies.""" - visitor = DependencyFinderVisitor() - for node in nodes: - visitor.visit(node) - for dependency in "filters", "tests": - mapping = getattr(self, dependency) - for name in getattr(visitor, dependency): - if name not in mapping: - mapping[name] = self.temporary_identifier() - self.writeline(f"{mapping[name]} = environment.{dependency}[{name!r}]") - - def enter_frame(self, frame): - undefs = [] - for target, (action, param) in frame.symbols.loads.items(): - if action == VAR_LOAD_PARAMETER: - pass - elif action == VAR_LOAD_RESOLVE: - self.writeline(f"{target} = {self.get_resolve_func()}({param!r})") - elif action == VAR_LOAD_ALIAS: - self.writeline(f"{target} = {param}") - elif action == VAR_LOAD_UNDEFINED: - undefs.append(target) - else: - raise NotImplementedError("unknown load instruction") - if undefs: - self.writeline(f"{' = '.join(undefs)} = missing") - - def leave_frame(self, frame, with_python_scope=False): - if not with_python_scope: - undefs = [] - for target in frame.symbols.loads: - undefs.append(target) - if undefs: - self.writeline(f"{' = '.join(undefs)} = missing") - - def func(self, name): - if self.environment.is_async: - return f"async def {name}" - return f"def {name}" - - def macro_body(self, node, frame): - """Dump the function def of a macro or call block.""" - frame = frame.inner() - frame.symbols.analyze_node(node) - macro_ref = MacroRef(node) - - explicit_caller = None - skip_special_params = set() - args = [] - for idx, arg in enumerate(node.args): - if arg.name == "caller": - explicit_caller = idx - if arg.name in ("kwargs", "varargs"): - skip_special_params.add(arg.name) - args.append(frame.symbols.ref(arg.name)) - - undeclared = find_undeclared(node.body, ("caller", "kwargs", "varargs")) - - if "caller" in undeclared: - # In older Jinja versions there was a bug that allowed caller - # to retain the special behavior even if it was mentioned in - # the argument list. However thankfully this was only really - # working if it was the last argument. So we are explicitly - # checking this now and error out if it is anywhere else in - # the argument list. - if explicit_caller is not None: - try: - node.defaults[explicit_caller - len(node.args)] - except IndexError: - self.fail( - "When defining macros or call blocks the " - 'special "caller" argument must be omitted ' - "or be given a default.", - node.lineno, - ) - else: - args.append(frame.symbols.declare_parameter("caller")) - macro_ref.accesses_caller = True - if "kwargs" in undeclared and "kwargs" not in skip_special_params: - args.append(frame.symbols.declare_parameter("kwargs")) - macro_ref.accesses_kwargs = True - if "varargs" in undeclared and "varargs" not in skip_special_params: - args.append(frame.symbols.declare_parameter("varargs")) - macro_ref.accesses_varargs = True - - # macros are delayed, they never require output checks - frame.require_output_check = False - frame.symbols.analyze_node(node) - self.writeline(f"{self.func('macro')}({', '.join(args)}):", node) - self.indent() - - self.buffer(frame) - self.enter_frame(frame) - - self.push_parameter_definitions(frame) - for idx, arg in enumerate(node.args): - ref = frame.symbols.ref(arg.name) - self.writeline(f"if {ref} is missing:") - self.indent() - try: - default = node.defaults[idx - len(node.args)] - except IndexError: - self.writeline( - f'{ref} = undefined("parameter {arg.name!r} was not provided",' - f" name={arg.name!r})" - ) - else: - self.writeline(f"{ref} = ") - self.visit(default, frame) - self.mark_parameter_stored(ref) - self.outdent() - self.pop_parameter_definitions() - - self.blockvisit(node.body, frame) - self.return_buffer_contents(frame, force_unescaped=True) - self.leave_frame(frame, with_python_scope=True) - self.outdent() - - return frame, macro_ref - - def macro_def(self, macro_ref, frame): - """Dump the macro definition for the def created by macro_body.""" - arg_tuple = ", ".join(repr(x.name) for x in macro_ref.node.args) - name = getattr(macro_ref.node, "name", None) - if len(macro_ref.node.args) == 1: - arg_tuple += "," - self.write( - f"Macro(environment, macro, {name!r}, ({arg_tuple})," - f" {macro_ref.accesses_kwargs!r}, {macro_ref.accesses_varargs!r}," - f" {macro_ref.accesses_caller!r}, context.eval_ctx.autoescape)" - ) - - def position(self, node): - """Return a human readable position for the node.""" - rv = f"line {node.lineno}" - if self.name is not None: - rv = f"{rv} in {self.name!r}" - return rv - - def dump_local_context(self, frame): - items_kv = ", ".join( - f"{name!r}: {target}" - for name, target in frame.symbols.dump_stores().items() - ) - return f"{{{items_kv}}}" - - def write_commons(self): - """Writes a common preamble that is used by root and block functions. - Primarily this sets up common local helpers and enforces a generator - through a dead branch. - """ - self.writeline("resolve = context.resolve_or_missing") - self.writeline("undefined = environment.undefined") - # always use the standard Undefined class for the implicit else of - # conditional expressions - self.writeline("cond_expr_undefined = Undefined") - self.writeline("if 0: yield None") - - def push_parameter_definitions(self, frame): - """Pushes all parameter targets from the given frame into a local - stack that permits tracking of yet to be assigned parameters. In - particular this enables the optimization from `visit_Name` to skip - undefined expressions for parameters in macros as macros can reference - otherwise unbound parameters. - """ - self._param_def_block.append(frame.symbols.dump_param_targets()) - - def pop_parameter_definitions(self): - """Pops the current parameter definitions set.""" - self._param_def_block.pop() - - def mark_parameter_stored(self, target): - """Marks a parameter in the current parameter definitions as stored. - This will skip the enforced undefined checks. - """ - if self._param_def_block: - self._param_def_block[-1].discard(target) - - def push_context_reference(self, target): - self._context_reference_stack.append(target) - - def pop_context_reference(self): - self._context_reference_stack.pop() - - def get_context_ref(self): - return self._context_reference_stack[-1] - - def get_resolve_func(self): - target = self._context_reference_stack[-1] - if target == "context": - return "resolve" - return f"{target}.resolve" - - def derive_context(self, frame): - return f"{self.get_context_ref()}.derived({self.dump_local_context(frame)})" - - def parameter_is_undeclared(self, target): - """Checks if a given target is an undeclared parameter.""" - if not self._param_def_block: - return False - return target in self._param_def_block[-1] - - def push_assign_tracking(self): - """Pushes a new layer for assignment tracking.""" - self._assign_stack.append(set()) - - def pop_assign_tracking(self, frame): - """Pops the topmost level for assignment tracking and updates the - context variables if necessary. - """ - vars = self._assign_stack.pop() - if not frame.toplevel or not vars: - return - public_names = [x for x in vars if x[:1] != "_"] - if len(vars) == 1: - name = next(iter(vars)) - ref = frame.symbols.ref(name) - self.writeline(f"context.vars[{name!r}] = {ref}") - else: - self.writeline("context.vars.update({") - for idx, name in enumerate(vars): - if idx: - self.write(", ") - ref = frame.symbols.ref(name) - self.write(f"{name!r}: {ref}") - self.write("})") - if public_names: - if len(public_names) == 1: - self.writeline(f"context.exported_vars.add({public_names[0]!r})") - else: - names_str = ", ".join(map(repr, public_names)) - self.writeline(f"context.exported_vars.update(({names_str}))") - - # -- Statement Visitors - - def visit_Template(self, node, frame=None): - assert frame is None, "no root frame allowed" - eval_ctx = EvalContext(self.environment, self.name) - - from .runtime import exported - - self.writeline("from __future__ import generator_stop") # Python < 3.7 - self.writeline("from jinja2.runtime import " + ", ".join(exported)) - - if self.environment.is_async: - self.writeline( - "from jinja2.asyncsupport import auto_await, " - "auto_aiter, AsyncLoopContext" - ) - - # if we want a deferred initialization we cannot move the - # environment into a local name - envenv = "" if self.defer_init else ", environment=environment" - - # do we have an extends tag at all? If not, we can save some - # overhead by just not processing any inheritance code. - have_extends = node.find(nodes.Extends) is not None - - # find all blocks - for block in node.find_all(nodes.Block): - if block.name in self.blocks: - self.fail(f"block {block.name!r} defined twice", block.lineno) - self.blocks[block.name] = block - - # find all imports and import them - for import_ in node.find_all(nodes.ImportedName): - if import_.importname not in self.import_aliases: - imp = import_.importname - self.import_aliases[imp] = alias = self.temporary_identifier() - if "." in imp: - module, obj = imp.rsplit(".", 1) - self.writeline(f"from {module} import {obj} as {alias}") - else: - self.writeline(f"import {imp} as {alias}") - - # add the load name - self.writeline(f"name = {self.name!r}") - - # generate the root render function. - self.writeline( - f"{self.func('root')}(context, missing=missing{envenv}):", extra=1 - ) - self.indent() - self.write_commons() - - # process the root - frame = Frame(eval_ctx) - if "self" in find_undeclared(node.body, ("self",)): - ref = frame.symbols.declare_parameter("self") - self.writeline(f"{ref} = TemplateReference(context)") - frame.symbols.analyze_node(node) - frame.toplevel = frame.rootlevel = True - frame.require_output_check = have_extends and not self.has_known_extends - if have_extends: - self.writeline("parent_template = None") - self.enter_frame(frame) - self.pull_dependencies(node.body) - self.blockvisit(node.body, frame) - self.leave_frame(frame, with_python_scope=True) - self.outdent() - - # make sure that the parent root is called. - if have_extends: - if not self.has_known_extends: - self.indent() - self.writeline("if parent_template is not None:") - self.indent() - if not self.environment.is_async: - self.writeline("yield from parent_template.root_render_func(context)") - else: - loop = "async for" if self.environment.is_async else "for" - self.writeline( - f"{loop} event in parent_template.root_render_func(context):" - ) - self.indent() - self.writeline("yield event") - self.outdent() - self.outdent(1 + (not self.has_known_extends)) - - # at this point we now have the blocks collected and can visit them too. - for name, block in self.blocks.items(): - self.writeline( - f"{self.func('block_' + name)}(context, missing=missing{envenv}):", - block, - 1, - ) - self.indent() - self.write_commons() - # It's important that we do not make this frame a child of the - # toplevel template. This would cause a variety of - # interesting issues with identifier tracking. - block_frame = Frame(eval_ctx) - undeclared = find_undeclared(block.body, ("self", "super")) - if "self" in undeclared: - ref = block_frame.symbols.declare_parameter("self") - self.writeline(f"{ref} = TemplateReference(context)") - if "super" in undeclared: - ref = block_frame.symbols.declare_parameter("super") - self.writeline(f"{ref} = context.super({name!r}, block_{name})") - block_frame.symbols.analyze_node(block) - block_frame.block = name - self.enter_frame(block_frame) - self.pull_dependencies(block.body) - self.blockvisit(block.body, block_frame) - self.leave_frame(block_frame, with_python_scope=True) - self.outdent() - - blocks_kv_str = ", ".join(f"{x!r}: block_{x}" for x in self.blocks) - self.writeline(f"blocks = {{{blocks_kv_str}}}", extra=1) - debug_kv_str = "&".join(f"{k}={v}" for k, v in self.debug_info) - self.writeline(f"debug_info = {debug_kv_str!r}") - - def visit_Block(self, node, frame): - """Call a block and register it for the template.""" - level = 0 - if frame.toplevel: - # if we know that we are a child template, there is no need to - # check if we are one - if self.has_known_extends: - return - if self.extends_so_far > 0: - self.writeline("if parent_template is None:") - self.indent() - level += 1 - - if node.scoped: - context = self.derive_context(frame) - else: - context = self.get_context_ref() - - if not self.environment.is_async and frame.buffer is None: - self.writeline( - f"yield from context.blocks[{node.name!r}][0]({context})", node - ) - else: - loop = "async for" if self.environment.is_async else "for" - self.writeline( - f"{loop} event in context.blocks[{node.name!r}][0]({context}):", node - ) - self.indent() - self.simple_write("event", frame) - self.outdent() - - self.outdent(level) - - def visit_Extends(self, node, frame): - """Calls the extender.""" - if not frame.toplevel: - self.fail("cannot use extend from a non top-level scope", node.lineno) - - # if the number of extends statements in general is zero so - # far, we don't have to add a check if something extended - # the template before this one. - if self.extends_so_far > 0: - - # if we have a known extends we just add a template runtime - # error into the generated code. We could catch that at compile - # time too, but i welcome it not to confuse users by throwing the - # same error at different times just "because we can". - if not self.has_known_extends: - self.writeline("if parent_template is not None:") - self.indent() - self.writeline('raise TemplateRuntimeError("extended multiple times")') - - # if we have a known extends already we don't need that code here - # as we know that the template execution will end here. - if self.has_known_extends: - raise CompilerExit() - else: - self.outdent() - - self.writeline("parent_template = environment.get_template(", node) - self.visit(node.template, frame) - self.write(f", {self.name!r})") - self.writeline("for name, parent_block in parent_template.blocks.items():") - self.indent() - self.writeline("context.blocks.setdefault(name, []).append(parent_block)") - self.outdent() - - # if this extends statement was in the root level we can take - # advantage of that information and simplify the generated code - # in the top level from this point onwards - if frame.rootlevel: - self.has_known_extends = True - - # and now we have one more - self.extends_so_far += 1 - - def visit_Include(self, node, frame): - """Handles includes.""" - if node.ignore_missing: - self.writeline("try:") - self.indent() - - func_name = "get_or_select_template" - if isinstance(node.template, nodes.Const): - if isinstance(node.template.value, str): - func_name = "get_template" - elif isinstance(node.template.value, (tuple, list)): - func_name = "select_template" - elif isinstance(node.template, (nodes.Tuple, nodes.List)): - func_name = "select_template" - - self.writeline(f"template = environment.{func_name}(", node) - self.visit(node.template, frame) - self.write(f", {self.name!r})") - if node.ignore_missing: - self.outdent() - self.writeline("except TemplateNotFound:") - self.indent() - self.writeline("pass") - self.outdent() - self.writeline("else:") - self.indent() - - skip_event_yield = False - if node.with_context: - loop = "async for" if self.environment.is_async else "for" - self.writeline( - f"{loop} event in template.root_render_func(" - "template.new_context(context.get_all(), True," - f" {self.dump_local_context(frame)})):" - ) - elif self.environment.is_async: - self.writeline( - "for event in (await template._get_default_module_async())" - "._body_stream:" - ) - else: - self.writeline("yield from template._get_default_module()._body_stream") - skip_event_yield = True - - if not skip_event_yield: - self.indent() - self.simple_write("event", frame) - self.outdent() - - if node.ignore_missing: - self.outdent() - - def visit_Import(self, node, frame): - """Visit regular imports.""" - self.writeline(f"{frame.symbols.ref(node.target)} = ", node) - if frame.toplevel: - self.write(f"context.vars[{node.target!r}] = ") - if self.environment.is_async: - self.write("await ") - self.write("environment.get_template(") - self.visit(node.template, frame) - self.write(f", {self.name!r}).") - if node.with_context: - func = "make_module" + ("_async" if self.environment.is_async else "") - self.write( - f"{func}(context.get_all(), True, {self.dump_local_context(frame)})" - ) - elif self.environment.is_async: - self.write("_get_default_module_async()") - else: - self.write("_get_default_module(context)") - if frame.toplevel and not node.target.startswith("_"): - self.writeline(f"context.exported_vars.discard({node.target!r})") - - def visit_FromImport(self, node, frame): - """Visit named imports.""" - self.newline(node) - prefix = "await " if self.environment.is_async else "" - self.write(f"included_template = {prefix}environment.get_template(") - self.visit(node.template, frame) - self.write(f", {self.name!r}).") - if node.with_context: - func = "make_module" + ("_async" if self.environment.is_async else "") - self.write( - f"{func}(context.get_all(), True, {self.dump_local_context(frame)})" - ) - elif self.environment.is_async: - self.write("_get_default_module_async()") - else: - self.write("_get_default_module(context)") - - var_names = [] - discarded_names = [] - for name in node.names: - if isinstance(name, tuple): - name, alias = name - else: - alias = name - self.writeline( - f"{frame.symbols.ref(alias)} =" - f" getattr(included_template, {name!r}, missing)" - ) - self.writeline(f"if {frame.symbols.ref(alias)} is missing:") - self.indent() - message = ( - "the template {included_template.__name__!r}" - f" (imported on {self.position(node)})" - f" does not export the requested name {name!r}" - ) - self.writeline( - f"{frame.symbols.ref(alias)} = undefined(f{message!r}, name={name!r})" - ) - self.outdent() - if frame.toplevel: - var_names.append(alias) - if not alias.startswith("_"): - discarded_names.append(alias) - - if var_names: - if len(var_names) == 1: - name = var_names[0] - self.writeline(f"context.vars[{name!r}] = {frame.symbols.ref(name)}") - else: - names_kv = ", ".join( - f"{name!r}: {frame.symbols.ref(name)}" for name in var_names - ) - self.writeline(f"context.vars.update({{{names_kv}}})") - if discarded_names: - if len(discarded_names) == 1: - self.writeline(f"context.exported_vars.discard({discarded_names[0]!r})") - else: - names_str = ", ".join(map(repr, discarded_names)) - self.writeline( - f"context.exported_vars.difference_update(({names_str}))" - ) - - def visit_For(self, node, frame): - loop_frame = frame.inner() - test_frame = frame.inner() - else_frame = frame.inner() - - # try to figure out if we have an extended loop. An extended loop - # is necessary if the loop is in recursive mode if the special loop - # variable is accessed in the body. - extended_loop = node.recursive or "loop" in find_undeclared( - node.iter_child_nodes(only=("body",)), ("loop",) - ) - - loop_ref = None - if extended_loop: - loop_ref = loop_frame.symbols.declare_parameter("loop") - - loop_frame.symbols.analyze_node(node, for_branch="body") - if node.else_: - else_frame.symbols.analyze_node(node, for_branch="else") - - if node.test: - loop_filter_func = self.temporary_identifier() - test_frame.symbols.analyze_node(node, for_branch="test") - self.writeline(f"{self.func(loop_filter_func)}(fiter):", node.test) - self.indent() - self.enter_frame(test_frame) - self.writeline("async for " if self.environment.is_async else "for ") - self.visit(node.target, loop_frame) - self.write(" in ") - self.write("auto_aiter(fiter)" if self.environment.is_async else "fiter") - self.write(":") - self.indent() - self.writeline("if ", node.test) - self.visit(node.test, test_frame) - self.write(":") - self.indent() - self.writeline("yield ") - self.visit(node.target, loop_frame) - self.outdent(3) - self.leave_frame(test_frame, with_python_scope=True) - - # if we don't have an recursive loop we have to find the shadowed - # variables at that point. Because loops can be nested but the loop - # variable is a special one we have to enforce aliasing for it. - if node.recursive: - self.writeline( - f"{self.func('loop')}(reciter, loop_render_func, depth=0):", node - ) - self.indent() - self.buffer(loop_frame) - - # Use the same buffer for the else frame - else_frame.buffer = loop_frame.buffer - - # make sure the loop variable is a special one and raise a template - # assertion error if a loop tries to write to loop - if extended_loop: - self.writeline(f"{loop_ref} = missing") - - for name in node.find_all(nodes.Name): - if name.ctx == "store" and name.name == "loop": - self.fail( - "Can't assign to special loop variable in for-loop target", - name.lineno, - ) - - if node.else_: - iteration_indicator = self.temporary_identifier() - self.writeline(f"{iteration_indicator} = 1") - - self.writeline("async for " if self.environment.is_async else "for ", node) - self.visit(node.target, loop_frame) - if extended_loop: - prefix = "Async" if self.environment.is_async else "" - self.write(f", {loop_ref} in {prefix}LoopContext(") - else: - self.write(" in ") - - if node.test: - self.write(f"{loop_filter_func}(") - if node.recursive: - self.write("reciter") - else: - if self.environment.is_async and not extended_loop: - self.write("auto_aiter(") - self.visit(node.iter, frame) - if self.environment.is_async and not extended_loop: - self.write(")") - if node.test: - self.write(")") - - if node.recursive: - self.write(", undefined, loop_render_func, depth):") - else: - self.write(", undefined):" if extended_loop else ":") - - self.indent() - self.enter_frame(loop_frame) - - self.blockvisit(node.body, loop_frame) - if node.else_: - self.writeline(f"{iteration_indicator} = 0") - self.outdent() - self.leave_frame( - loop_frame, with_python_scope=node.recursive and not node.else_ - ) - - if node.else_: - self.writeline(f"if {iteration_indicator}:") - self.indent() - self.enter_frame(else_frame) - self.blockvisit(node.else_, else_frame) - self.leave_frame(else_frame) - self.outdent() - - # if the node was recursive we have to return the buffer contents - # and start the iteration code - if node.recursive: - self.return_buffer_contents(loop_frame) - self.outdent() - self.start_write(frame, node) - if self.environment.is_async: - self.write("await ") - self.write("loop(") - if self.environment.is_async: - self.write("auto_aiter(") - self.visit(node.iter, frame) - if self.environment.is_async: - self.write(")") - self.write(", loop)") - self.end_write(frame) - - def visit_If(self, node, frame): - if_frame = frame.soft() - self.writeline("if ", node) - self.visit(node.test, if_frame) - self.write(":") - self.indent() - self.blockvisit(node.body, if_frame) - self.outdent() - for elif_ in node.elif_: - self.writeline("elif ", elif_) - self.visit(elif_.test, if_frame) - self.write(":") - self.indent() - self.blockvisit(elif_.body, if_frame) - self.outdent() - if node.else_: - self.writeline("else:") - self.indent() - self.blockvisit(node.else_, if_frame) - self.outdent() - - def visit_Macro(self, node, frame): - macro_frame, macro_ref = self.macro_body(node, frame) - self.newline() - if frame.toplevel: - if not node.name.startswith("_"): - self.write(f"context.exported_vars.add({node.name!r})") - self.writeline(f"context.vars[{node.name!r}] = ") - self.write(f"{frame.symbols.ref(node.name)} = ") - self.macro_def(macro_ref, macro_frame) - - def visit_CallBlock(self, node, frame): - call_frame, macro_ref = self.macro_body(node, frame) - self.writeline("caller = ") - self.macro_def(macro_ref, call_frame) - self.start_write(frame, node) - self.visit_Call(node.call, frame, forward_caller=True) - self.end_write(frame) - - def visit_FilterBlock(self, node, frame): - filter_frame = frame.inner() - filter_frame.symbols.analyze_node(node) - self.enter_frame(filter_frame) - self.buffer(filter_frame) - self.blockvisit(node.body, filter_frame) - self.start_write(frame, node) - self.visit_Filter(node.filter, filter_frame) - self.end_write(frame) - self.leave_frame(filter_frame) - - def visit_With(self, node, frame): - with_frame = frame.inner() - with_frame.symbols.analyze_node(node) - self.enter_frame(with_frame) - for target, expr in zip(node.targets, node.values): - self.newline() - self.visit(target, with_frame) - self.write(" = ") - self.visit(expr, frame) - self.blockvisit(node.body, with_frame) - self.leave_frame(with_frame) - - def visit_ExprStmt(self, node, frame): - self.newline(node) - self.visit(node.node, frame) - - _FinalizeInfo = namedtuple("_FinalizeInfo", ("const", "src")) - #: The default finalize function if the environment isn't configured - #: with one. Or if the environment has one, this is called on that - #: function's output for constants. - _default_finalize = str - _finalize = None - - def _make_finalize(self): - """Build the finalize function to be used on constants and at - runtime. Cached so it's only created once for all output nodes. - - Returns a ``namedtuple`` with the following attributes: - - ``const`` - A function to finalize constant data at compile time. - - ``src`` - Source code to output around nodes to be evaluated at - runtime. - """ - if self._finalize is not None: - return self._finalize - - finalize = default = self._default_finalize - src = None - - if self.environment.finalize: - src = "environment.finalize(" - env_finalize = self.environment.finalize - - def finalize(value): - return default(env_finalize(value)) - - if getattr(env_finalize, "contextfunction", False) is True: - src += "context, " - finalize = None # noqa: F811 - elif getattr(env_finalize, "evalcontextfunction", False) is True: - src += "context.eval_ctx, " - finalize = None - elif getattr(env_finalize, "environmentfunction", False) is True: - src += "environment, " - - def finalize(value): - return default(env_finalize(self.environment, value)) - - self._finalize = self._FinalizeInfo(finalize, src) - return self._finalize - - def _output_const_repr(self, group): - """Given a group of constant values converted from ``Output`` - child nodes, produce a string to write to the template module - source. - """ - return repr(concat(group)) - - def _output_child_to_const(self, node, frame, finalize): - """Try to optimize a child of an ``Output`` node by trying to - convert it to constant, finalized data at compile time. - - If :exc:`Impossible` is raised, the node is not constant and - will be evaluated at runtime. Any other exception will also be - evaluated at runtime for easier debugging. - """ - const = node.as_const(frame.eval_ctx) - - if frame.eval_ctx.autoescape: - const = escape(const) - - # Template data doesn't go through finalize. - if isinstance(node, nodes.TemplateData): - return str(const) - - return finalize.const(const) - - def _output_child_pre(self, node, frame, finalize): - """Output extra source code before visiting a child of an - ``Output`` node. - """ - if frame.eval_ctx.volatile: - self.write("(escape if context.eval_ctx.autoescape else str)(") - elif frame.eval_ctx.autoescape: - self.write("escape(") - else: - self.write("str(") - - if finalize.src is not None: - self.write(finalize.src) - - def _output_child_post(self, node, frame, finalize): - """Output extra source code after visiting a child of an - ``Output`` node. - """ - self.write(")") - - if finalize.src is not None: - self.write(")") - - def visit_Output(self, node, frame): - # If an extends is active, don't render outside a block. - if frame.require_output_check: - # A top-level extends is known to exist at compile time. - if self.has_known_extends: - return - - self.writeline("if parent_template is None:") - self.indent() - - finalize = self._make_finalize() - body = [] - - # Evaluate constants at compile time if possible. Each item in - # body will be either a list of static data or a node to be - # evaluated at runtime. - for child in node.nodes: - try: - if not ( - # If the finalize function requires runtime context, - # constants can't be evaluated at compile time. - finalize.const - # Unless it's basic template data that won't be - # finalized anyway. - or isinstance(child, nodes.TemplateData) - ): - raise nodes.Impossible() - - const = self._output_child_to_const(child, frame, finalize) - except (nodes.Impossible, Exception): - # The node was not constant and needs to be evaluated at - # runtime. Or another error was raised, which is easier - # to debug at runtime. - body.append(child) - continue - - if body and isinstance(body[-1], list): - body[-1].append(const) - else: - body.append([const]) - - if frame.buffer is not None: - if len(body) == 1: - self.writeline(f"{frame.buffer}.append(") - else: - self.writeline(f"{frame.buffer}.extend((") - - self.indent() - - for item in body: - if isinstance(item, list): - # A group of constant data to join and output. - val = self._output_const_repr(item) - - if frame.buffer is None: - self.writeline("yield " + val) - else: - self.writeline(val + ",") - else: - if frame.buffer is None: - self.writeline("yield ", item) - else: - self.newline(item) - - # A node to be evaluated at runtime. - self._output_child_pre(item, frame, finalize) - self.visit(item, frame) - self._output_child_post(item, frame, finalize) - - if frame.buffer is not None: - self.write(",") - - if frame.buffer is not None: - self.outdent() - self.writeline(")" if len(body) == 1 else "))") - - if frame.require_output_check: - self.outdent() - - def visit_Assign(self, node, frame): - self.push_assign_tracking() - self.newline(node) - self.visit(node.target, frame) - self.write(" = ") - self.visit(node.node, frame) - self.pop_assign_tracking(frame) - - def visit_AssignBlock(self, node, frame): - self.push_assign_tracking() - block_frame = frame.inner() - # This is a special case. Since a set block always captures we - # will disable output checks. This way one can use set blocks - # toplevel even in extended templates. - block_frame.require_output_check = False - block_frame.symbols.analyze_node(node) - self.enter_frame(block_frame) - self.buffer(block_frame) - self.blockvisit(node.body, block_frame) - self.newline(node) - self.visit(node.target, frame) - self.write(" = (Markup if context.eval_ctx.autoescape else identity)(") - if node.filter is not None: - self.visit_Filter(node.filter, block_frame) - else: - self.write(f"concat({block_frame.buffer})") - self.write(")") - self.pop_assign_tracking(frame) - self.leave_frame(block_frame) - - # -- Expression Visitors - - def visit_Name(self, node, frame): - if node.ctx == "store" and frame.toplevel: - if self._assign_stack: - self._assign_stack[-1].add(node.name) - ref = frame.symbols.ref(node.name) - - # If we are looking up a variable we might have to deal with the - # case where it's undefined. We can skip that case if the load - # instruction indicates a parameter which are always defined. - if node.ctx == "load": - load = frame.symbols.find_load(ref) - if not ( - load is not None - and load[0] == VAR_LOAD_PARAMETER - and not self.parameter_is_undeclared(ref) - ): - self.write( - f"(undefined(name={node.name!r}) if {ref} is missing else {ref})" - ) - return - - self.write(ref) - - def visit_NSRef(self, node, frame): - # NSRefs can only be used to store values; since they use the normal - # `foo.bar` notation they will be parsed as a normal attribute access - # when used anywhere but in a `set` context - ref = frame.symbols.ref(node.name) - self.writeline(f"if not isinstance({ref}, Namespace):") - self.indent() - self.writeline( - "raise TemplateRuntimeError" - '("cannot assign attribute on non-namespace object")' - ) - self.outdent() - self.writeline(f"{ref}[{node.attr!r}]") - - def visit_Const(self, node, frame): - val = node.as_const(frame.eval_ctx) - if isinstance(val, float): - self.write(str(val)) - else: - self.write(repr(val)) - - def visit_TemplateData(self, node, frame): - try: - self.write(repr(node.as_const(frame.eval_ctx))) - except nodes.Impossible: - self.write( - f"(Markup if context.eval_ctx.autoescape else identity)({node.data!r})" - ) - - def visit_Tuple(self, node, frame): - self.write("(") - idx = -1 - for idx, item in enumerate(node.items): - if idx: - self.write(", ") - self.visit(item, frame) - self.write(",)" if idx == 0 else ")") - - def visit_List(self, node, frame): - self.write("[") - for idx, item in enumerate(node.items): - if idx: - self.write(", ") - self.visit(item, frame) - self.write("]") - - def visit_Dict(self, node, frame): - self.write("{") - for idx, item in enumerate(node.items): - if idx: - self.write(", ") - self.visit(item.key, frame) - self.write(": ") - self.visit(item.value, frame) - self.write("}") - - def binop(operator, interceptable=True): # noqa: B902 - @optimizeconst - def visitor(self, node, frame): - if ( - self.environment.sandboxed - and operator in self.environment.intercepted_binops - ): - self.write(f"environment.call_binop(context, {operator!r}, ") - self.visit(node.left, frame) - self.write(", ") - self.visit(node.right, frame) - else: - self.write("(") - self.visit(node.left, frame) - self.write(f" {operator} ") - self.visit(node.right, frame) - self.write(")") - - return visitor - - def uaop(operator, interceptable=True): # noqa: B902 - @optimizeconst - def visitor(self, node, frame): - if ( - self.environment.sandboxed - and operator in self.environment.intercepted_unops - ): - self.write(f"environment.call_unop(context, {operator!r}, ") - self.visit(node.node, frame) - else: - self.write("(" + operator) - self.visit(node.node, frame) - self.write(")") - - return visitor - - visit_Add = binop("+") - visit_Sub = binop("-") - visit_Mul = binop("*") - visit_Div = binop("/") - visit_FloorDiv = binop("//") - visit_Pow = binop("**") - visit_Mod = binop("%") - visit_And = binop("and", interceptable=False) - visit_Or = binop("or", interceptable=False) - visit_Pos = uaop("+") - visit_Neg = uaop("-") - visit_Not = uaop("not ", interceptable=False) - del binop, uaop - - @optimizeconst - def visit_Concat(self, node, frame): - if frame.eval_ctx.volatile: - func_name = "(markup_join if context.eval_ctx.volatile else str_join)" - elif frame.eval_ctx.autoescape: - func_name = "markup_join" - else: - func_name = "str_join" - self.write(f"{func_name}((") - for arg in node.nodes: - self.visit(arg, frame) - self.write(", ") - self.write("))") - - @optimizeconst - def visit_Compare(self, node, frame): - self.write("(") - self.visit(node.expr, frame) - for op in node.ops: - self.visit(op, frame) - self.write(")") - - def visit_Operand(self, node, frame): - self.write(f" {operators[node.op]} ") - self.visit(node.expr, frame) - - @optimizeconst - def visit_Getattr(self, node, frame): - if self.environment.is_async: - self.write("(await auto_await(") - - self.write("environment.getattr(") - self.visit(node.node, frame) - self.write(f", {node.attr!r})") - - if self.environment.is_async: - self.write("))") - - @optimizeconst - def visit_Getitem(self, node, frame): - # slices bypass the environment getitem method. - if isinstance(node.arg, nodes.Slice): - self.visit(node.node, frame) - self.write("[") - self.visit(node.arg, frame) - self.write("]") - else: - if self.environment.is_async: - self.write("(await auto_await(") - - self.write("environment.getitem(") - self.visit(node.node, frame) - self.write(", ") - self.visit(node.arg, frame) - self.write(")") - - if self.environment.is_async: - self.write("))") - - def visit_Slice(self, node, frame): - if node.start is not None: - self.visit(node.start, frame) - self.write(":") - if node.stop is not None: - self.visit(node.stop, frame) - if node.step is not None: - self.write(":") - self.visit(node.step, frame) - - @optimizeconst - def visit_Filter(self, node, frame): - if self.environment.is_async: - self.write("await auto_await(") - self.write(self.filters[node.name] + "(") - func = self.environment.filters.get(node.name) - if func is None: - self.fail(f"no filter named {node.name!r}", node.lineno) - if getattr(func, "contextfilter", False) is True: - self.write("context, ") - elif getattr(func, "evalcontextfilter", False) is True: - self.write("context.eval_ctx, ") - elif getattr(func, "environmentfilter", False) is True: - self.write("environment, ") - - # if the filter node is None we are inside a filter block - # and want to write to the current buffer - if node.node is not None: - self.visit(node.node, frame) - elif frame.eval_ctx.volatile: - self.write( - f"(Markup(concat({frame.buffer}))" - f" if context.eval_ctx.autoescape else concat({frame.buffer}))" - ) - elif frame.eval_ctx.autoescape: - self.write(f"Markup(concat({frame.buffer}))") - else: - self.write(f"concat({frame.buffer})") - self.signature(node, frame) - self.write(")") - if self.environment.is_async: - self.write(")") - - @optimizeconst - def visit_Test(self, node, frame): - self.write(self.tests[node.name] + "(") - if node.name not in self.environment.tests: - self.fail(f"no test named {node.name!r}", node.lineno) - self.visit(node.node, frame) - self.signature(node, frame) - self.write(")") - - @optimizeconst - def visit_CondExpr(self, node, frame): - def write_expr2(): - if node.expr2 is not None: - return self.visit(node.expr2, frame) - self.write( - f'cond_expr_undefined("the inline if-expression on' - f" {self.position(node)} evaluated to false and no else" - f' section was defined.")' - ) - - self.write("(") - self.visit(node.expr1, frame) - self.write(" if ") - self.visit(node.test, frame) - self.write(" else ") - write_expr2() - self.write(")") - - @optimizeconst - def visit_Call(self, node, frame, forward_caller=False): - if self.environment.is_async: - self.write("await auto_await(") - if self.environment.sandboxed: - self.write("environment.call(context, ") - else: - self.write("context.call(") - self.visit(node.node, frame) - extra_kwargs = {"caller": "caller"} if forward_caller else None - self.signature(node, frame, extra_kwargs) - self.write(")") - if self.environment.is_async: - self.write(")") - - def visit_Keyword(self, node, frame): - self.write(node.key + "=") - self.visit(node.value, frame) - - # -- Unused nodes for extensions - - def visit_MarkSafe(self, node, frame): - self.write("Markup(") - self.visit(node.expr, frame) - self.write(")") - - def visit_MarkSafeIfAutoescape(self, node, frame): - self.write("(Markup if context.eval_ctx.autoescape else identity)(") - self.visit(node.expr, frame) - self.write(")") - - def visit_EnvironmentAttribute(self, node, frame): - self.write("environment." + node.name) - - def visit_ExtensionAttribute(self, node, frame): - self.write(f"environment.extensions[{node.identifier!r}].{node.name}") - - def visit_ImportedName(self, node, frame): - self.write(self.import_aliases[node.importname]) - - def visit_InternalName(self, node, frame): - self.write(node.name) - - def visit_ContextReference(self, node, frame): - self.write("context") - - def visit_DerivedContextReference(self, node, frame): - self.write(self.derive_context(frame)) - - def visit_Continue(self, node, frame): - self.writeline("continue", node) - - def visit_Break(self, node, frame): - self.writeline("break", node) - - def visit_Scope(self, node, frame): - scope_frame = frame.inner() - scope_frame.symbols.analyze_node(node) - self.enter_frame(scope_frame) - self.blockvisit(node.body, scope_frame) - self.leave_frame(scope_frame) - - def visit_OverlayScope(self, node, frame): - ctx = self.temporary_identifier() - self.writeline(f"{ctx} = {self.derive_context(frame)}") - self.writeline(f"{ctx}.vars = ") - self.visit(node.context, frame) - self.push_context_reference(ctx) - - scope_frame = frame.inner(isolated=True) - scope_frame.symbols.analyze_node(node) - self.enter_frame(scope_frame) - self.blockvisit(node.body, scope_frame) - self.leave_frame(scope_frame) - self.pop_context_reference() - - def visit_EvalContextModifier(self, node, frame): - for keyword in node.options: - self.writeline(f"context.eval_ctx.{keyword.key} = ") - self.visit(keyword.value, frame) - try: - val = keyword.value.as_const(frame.eval_ctx) - except nodes.Impossible: - frame.eval_ctx.volatile = True - else: - setattr(frame.eval_ctx, keyword.key, val) - - def visit_ScopedEvalContextModifier(self, node, frame): - old_ctx_name = self.temporary_identifier() - saved_ctx = frame.eval_ctx.save() - self.writeline(f"{old_ctx_name} = context.eval_ctx.save()") - self.visit_EvalContextModifier(node, frame) - for child in node.body: - self.visit(child, frame) - frame.eval_ctx.revert(saved_ctx) - self.writeline(f"context.eval_ctx.revert({old_ctx_name})") |